Multiple implant constructions and fixation methods associated therewith

ABSTRACT

Using the simplified placement system and method for a tissue graft anchor of the present invention, a surgeon may introduce one or more sutures into a hole in a boney tissue, apply a precise amount of tension to the sutures to advance a soft tissue graft to a desired location, and then advance the anchor into the bone, preferably while maintaining the requisite pre-determined suture tension and without introducing spin to the suture. Particularly preferred embodiments of the present invention relate to multi-anchor constructs. Multi-anchor constructs of the present invention may employ threaded implants exclusively, push-in implants exclusively, or a combination of threaded and push-in implants.

PRIORITY

This application is a continuation of U.S. patent application Ser. No.15/256,945, filed Sep. 6, 2016 (now U.S. Pat. No. 9,717,587 issued Aug.1, 2017), which, in turn is a continuation-in-part of U.S. patentapplication Ser. No. 15/012,060 filed Feb. 1, 2016 (now U.S. Pat. No.9,566,060 issued Feb. 14, 2017), which, in turn, is acontinuation-in-part of U.S. patent application Ser. No. 14/972,662filed Dec. 17, 2015, which, in turn, is a continuation of U.S. patentapplication Ser. No. 14/636,389 filed Mar. 3, 2015 (now U.S. Pat. No.9,226,817 issued Jan. 5, 2016), which, in turn, claims the benefit ofU.S. Provisional Application Ser. No. 61/966,744 filed Mar. 3, 2014;61/998,391 filed Jun. 26, 2014; 61/998,766 filed Jul. 7, 2014; and61/999,405 filed Jul. 26, 2014, the contents of each of which are herebyincorporated by reference in their entirety. This application alsoclaims the benefit of U.S. Provisional Application Ser. No. 62/284,151filed Sep. 21, 2015 and 62/389,039 filed Feb. 16, 2016. The contents ofthe afore-noted priority applications are hereby incorporated byreference in their entirety.

TECHNICAL FIELD OF THE INVENTION

The present invention relates generally to the field of endoscopic andarthroscopic surgery and suture anchor systems for use therein. Moreparticularly, the invention relates to knotless suture anchor systemsand methods utilized to secure a soft tissue to boney surface throughthe placement of a matrix of implants. Specifically, the inventionrelates to simplified methods by which the surgeon may producemulti-implant constructs for the purpose of compressing a portion of atissue graft to a boney surface for the purpose of reattachment theretothrough healing.

BACKGROUND OF THE INVENTION

The use of implants to affix tissue grafts to bone is well known in theorthopedic arts. Common procedures in which such implants are usedinclude, for example, the repair of rotator cuff tears, and the repairof torn ligaments in the knee, among others. In these procedures, asocket is drilled or punched in the bone at the attachment site and agraft is secured to the bone using an implant placed in the socket. Thegraft may be secured to the implant by sutures, or, alternatively, anend of the graft may be placed in the socket and secured directly by animplant.

In rotator cuff repair implants commonly referred to as “anchors” areused. These anchors occur in two types: conventional anchors in whichthe suture is passed through the cuff after anchor placement, and“knotless” anchors in which the suture is passed through the cuff priorto anchor placement. In the former case, the graft is secured in placeby tying knots in the suture after it has been passed through the cuffso as to secure the cuff in the desired location. Conversely, as thename implies, when using a knotless anchor the sutures are passedthrough the cuff and through a feature of the anchor such that when theanchor is inserted into the socket, the suture position is secured bythe anchor. The tying of knots is not required. This is particularlyadvantageous when performing endoscopic (arthroscopic) repairs since thetying of knots arthroscopically through a small diameter cannula may bedifficult for some surgeons and, moreover, there is an opportunity fortangling of the sutures.

Many anchors, both conventional and knotless, are supplied to thesurgeon mounted on a driver—a device that the surgeon uses to place theanchor in the prepared socket in the bone. In the case of threadedanchors, the driver has a form like that of a screwdriver, and indeedfunctions in the same manner. The proximal portion of the device forms ahandle that is grasped by the surgeon. Distal to the handle, an elongatedistal portion has formed at its distal end features for transmittingtorque to an implant. Some anchors, generally metallic anchors such as,for instance, the Revo® Suture Anchor by Conmed Corporation (Utica,N.Y.) and Ti-Screw Suture Anchor by Biomet Corporation (Warsaw, Ind.),have a protruding (male) proximal portion with a cross-section suitablefor transmitting torque (typically hexagonal or square) and a transverseeyelet formed therein. The driver for such devices has a complimentarysocket (female) formed in its distal end and a cannulation that extendsfrom the interior of the socket to the proximal handle portion of thedevice. Sutures loaded into the eyelet of the anchor extend through thedriver cannulation (or “lumen”) and are removably secured to the handleso as to retain the anchor in the socket of the driver. Such anchors arereferred to in the orthopedic arts as “pre-loaded”, meaning that suturescome loaded into an anchor that is ready for placement by the surgeonusing the associated driver.

Other threaded anchors have a socket (female) formed in their proximalends. Once again, the socket has a cross-section suitable fortransmitting torque that is typically polygonal, usually square orhexagonal. Typical of these are the V-LoX™ family of titanium sutureanchors by Parcus Medical (Sarasota, Fla.) and the ALLthread™ anchors byBiomet Corporation (Warsaw, Ind.). The drivers for such devices have aprotruding (male) torque-transmitting feature complementary to thesocket (female) formed in the proximal end of the anchor. These driversmay be cannulated to accommodate sutures that are preloaded into theanchor in the manner previously described, with the sutures being eitherfor the purpose of securing tissue after anchor placement, or for thepurpose of removably securing the anchor to the driver, wherein thesutures are released from the driver after the anchor is placed in thebone and subsequently removed and discarded so as to allow removal ofthe driver from the anchor. The depth of the socket in the proximal endof the implant must be sufficient to enable transmission of therequisite torque needed for anchor placement without deforming orfracturing the implant. As the maximum depth of the torque-transmittingportion is generally limited only by the configuration of the anchor, itis considered to be matter of design choice. Indeed, the implant mayhave a cannulation that extends axially through the implant as well as atorque-transmitting cross-section forming a substantial proximal portionor the entirety of the implant's length. Implants of the Bio-TenodesisScrew™ System by Arthrex, Inc have a cannulation with a constanttorque-transmitting cross-section, and are used with a driver having atorque-transmitting portion that extends beyond the distal end of theanchor, wherein the portion of the driver extending beyond the anchorand a suture loop in the driver cannulation are used together to insertthe end of a graft into a prepared socket prior to placement of theimplant.

Knotless suture anchor fixation is a common way of repairing soft tissuethat has been torn from bone. Illustrative examples of such “knotless”anchors include the Allthread™ Knotless Anchors by Biomet Incorporated(Warsaw, Ind.), the SwiveLock® Knotless Anchor system by Arthrex,Incorporated (Naples, Fla.), the HEALIX Knotless™ Anchors byDepuy/Mitek, Incorporated (Raynham, Mass.) and the Knotless Push-InAnchors such as the Knotless PEEK CF Anchor by Parcus Medical (Sarasota,Fla.). The procedure requires drilling or punching of holes into aproperly prepared boney surface. After suture has been passed throughsoft tissue the suture anchor is introduced into the socket and driveninto the socket using a mallet or by screwing the anchor into the socketusing a driver device. These driver devices typically resemble ascrewdriver in form, having a proximal handle portion for applyingtorque or percussive force, and an elongate rigid distal portion havingat its distal end a torque or percussive force-transmittingconfiguration. In the case of torque-transmitting drivers used withthreaded anchors, the distal end of the driver typically has an elongatehexagonal or square distally extending portion that, through couplingwith a lumen in the anchor having a complementary cross-section,transmits torque to the anchor. The lumen may extend through anchor sothat the distal portion of the driver protrudes from the distal end ofthe anchor and rotates with the anchor during anchor placement.

Because the suture is drawn into the prepared socket along with theanchor during anchor placement, it is essential that a suitable lengthof suture extends between the graft and the anchor so that when theanchor is suitably positioned within the socket, the graft is properlypositioned. Determining the proper length of suture to allow between theanchor and the graft so as to achieve optimal graft positioning iscomplicated since suture may twist (a process referred to in theorthopedic arts as “suture spin”) during anchor placement, therebyshortening the effective length and changing the final graft positionand/or undesirably increasing the suture tension.

U.S. Pat. No. 6,544,281 to ElAttrache et al. describes a cannulatedanchor placement system having a rotating inner member (which acts asthe anchor driver) and a stationary outer member, wherein the rotatinginner member serves to drive the threaded anchor. The rotating “driver”extends past the distal end of the anchor and is inserted into aprepared socket in the boney surface. A suture loop formed distal to thedistal end of the driver “captures” or “secures” sutures attached to agraft or the graft itself to the distal end of the driver. The distalend of the driver is then inserted into the socket to a proper depth foranchor placement thereby drawing the graft to the desired position priorto placement of the anchor. The anchor is then threaded into the socketto the predetermined depth. This system constitutes an improvement overother commercially available alternatives. However, because the graft orsutures are secured to or pass through the distal end of the rotatinginner (or “driver”), torque is transmitted not only to the anchor butalso to the graft or sutures attached thereto by the suture loop.Accordingly, twisting of the sutures or graft frequently occurs, therebychanging the resulting suture tension and/or the graft position (aprocess referred to in the orthopedic arts as “graft shift”).

U.S. Pat. No. 8,663,279 by Burkhart et al. describes a knotless anchorsystem similar in construction to that of ElAttrache et al. A “swivel”implant having formed therein an eyelet is releasably and pivotablymounted to the distal end of a driver distal portion that extendsdistally beyond the distal end of an anchor. After sutures are passedthrough the graft, they are threaded into the eyelet of the swivelimplant at the distal end of the driver. The distal end of the driverwith the swivel implant is then inserted into the socket. By pulling onthe suture tails, the graft is moved into position and secured byscrewing the anchor into the socket. However, because the sutures/graftare secured to the driver by means of the swivel eyelet implant, thetorque that may be transmitted to the sutures/graft is limited. Torquetransmission is not eliminated since the swivel implant is retained inthe driver distal end by a suture loop under tension, which extendsthrough the cannula of the driver to the driver's proximal end where thesuture ends are cleated. While an improvement over the ElAttrache anchorsystem, suture spin is not eliminated in all cases, and indeed, cannotbe since the suture-retaining implant is mounted to the driver, whichrotates during anchor placement. As such, some level of torquetransmission due to friction between the driver distal end and theswivel eyelet implant is inevitable.

Other knotless anchors such as the ReelX STT™ Knotless Anchor System byStryker® Corporation (Kalamazoo, Mich.) and PopLok® Knotless Anchors byConMed Corporation (Utica, N.Y.) have complex constructions and requirethat the surgeon perform a sequence of steps to achieve a successfulanchor placement with the desired suture tension and proper cuffposition. The sequence of steps adds to procedure time and createsopportunities for failure of the placement procedure if a step is notperformed properly.

Accordingly, there is a need in the orthopedic arts for a knotlessanchor system that allows the surgeon to establish the graft position,and, while maintaining that position, place the anchor without changingthe suture tension or causing a shift in the graft position due tosuture spin. Furthermore, if the anchor is threaded, placement of theanchor in the socket must occur without spinning of the suture.

Fixation methods previously herein described, as well as in parentapplication Ser. No. 15/012,060 filed Feb. 1, 2016 and Ser. No.14/972,662 filed Dec. 17, 2015 cited above and incorporated by referenceherein, are used in what is generally referred to as “single row” repairof rotator cuff tears. Specifically, suture(s) placed through the cuffis/are secured to a single anchor lateral to the lateral margin of thecuff, the anchors forming a single row lateral to the cuff's edge.However, these single-row repair methods can achieve only partialrestoration of the original footprint of the tendons of the rotatorcuff. Accordingly, “double row” repairs of rotator cuff tears areincreasing in popularity. In such double row techniques, one or moresutures loaded to a first implant medial to the edge of the cuff is/arepassed over the cuff and affixed to a second implant, which is placedlateral to the edge of the cuff, the suture between the anchors beingtensioned so as to apply a compressive force to the tissue therebeneath.These double-row (DR) repair methods present many biomechanicaladvantages and exhibit higher rates of tendon-to-bone healing.

In U.S. Pat. Nos. 7,585,311 and 8,100,942, Green et al. describe doublerow techniques for rotator cuff repair. In particular, Green et al.teach a method in which a first anchor with sutures affixed thereto isplaced medial to the edge of the rotator cuff. Thereafter, a secondanchor is placed lateral to the edge of the cuff. Suture from the firstanchor is then passed over the cuff, tensioned, and then affixed to thesecond anchor. The second anchor is irremovably placed prior totensioning of the suture and fixation thereto.

When fixation of the suture in the anchor is complete, the tension inthe suture between the anchors is established, the suture beingirremovably affixed to the second anchor. If the tension is judged bythe surgeon to be unacceptable (i.e., either inadequate or too great),or if the placement location is unacceptable, it becomes necessary toprepare a socket in an alternate location and repeat the stepspreviously described since the suture is permanently affixed to theoriginally placed second anchor and the anchor is not readily removablefrom the socket. Critically, currently available implant systems cannotbe repositioned using the original anchor, nor can they be removed andreplaced without compromising the eyelet/anchor construct.

SUMMARY OF THE INVENTION

A primary objective of the present invention is to provide improvedmeans and methods of attaching soft tissues (i.e., “grafts”) to bone insitu. The embodiments of the instant invention are described hereinbelowas a system and method for producing a matrix of implants for theanchoring of a graft to bone. Any graft fixation system which uses animplant placement system with an optionally cannulated non-rotatingtensioning device (i.e., the relatively fixed “inner assembly”)positioned within a lumen of a cannulated driver (i.e., the relativelymovable “outer assembly”) to tension sutures in a prepared socket forthe placement of a simple one-piece cannulated anchor are contemplatedby the present invention. Illustrative aspects and embodiments of thepresent invention in accordance with the foregoing objective are asfollows: In a first aspect, the present invention provides prostheticimplants and systems for their placement in a target boney surface forthe knotless securing of a soft tissue graft thereto. The instantinvention contemplates a novel placement system including a non-rotatingcannulated tensioning device (“inner assembly”) positioned within arotationally and axially movable cannulated driver (“outer assembly”).In a preferred embodiment, a distal element of the tensioning deviceextends distally beyond the distal end of the cannulated driver. Acannulated threaded implant (or “anchor”) is removably mounted to thetorque-transmitting distal portion of the driver. Sutures placed in thegraft are drawn into the distal end of the elongate distal portion ofthe cannulated tensioning device, which extends beyond the distal end ofthe implant. If a threaded implant is used, the distal end of thecannulated driver preferably includes torque-transmitting features that,together with complementary features formed in the proximal portion ofthe implant or anchor, allow the transmission of torque thereto. If aninterference plug-type anchor is used, the distal end of the driver ispreferably configured to transmit axial force to the anchor, the distalend of which has suitable complementary features to enable secureattachment.

In operation, sutures placed in the graft are drawn into the distal endof the tensioning device. The elongate distal portion of tensioningdevice is inserted into a properly prepared socket in the target boneysurface so that the distal end of the tensioning device, with itssutures is positioned at the bottom of the socket. Tension is thenapplied to the sutures by pulling on their proximal ends, which extendbeyond the proximal portion of the tensioning device to move the graftinto the desired position, namely into the prepared socket adjacent tothe distal element of the tensioning device. The desired tension may bemaintained by cleating proximal portions of the suture(s) into slotsoptionally formed in the handle of the tensioning device. The anchor (orinterference screw) may then be screwed, threaded or otherwise driveninto the socket, thereby trapping the sutures or graft between theanchor exterior surface and the socket wall. Critically, twisting of thesutures or graft is prevented by the non-rotating distal portion of thetensioning device that remains distal to the anchor distal end duringanchor placement. In addition, tension on the sutures and the positionof the graft are maintained during placement of the anchor throughoutthe procedure. After anchor placement, the driver and tensioning deviceare withdrawn, removed from the site, at which point the sutures may betrimmed to complete the procedure.

In contrast to the Burkhart and ElAttrache anchor systems, suturetensioning and establishment of the graft position are not accomplishedusing the driver's distal end or using an implant positioned in thedriver's distal end. Rather, suture tension and graft position areestablished and maintained by the distal portion of a non-rotatingtensioning device that extends beyond the driver and anchor distal ends.Because of this, the transmission of torque to the sutures and/or graftby the driver present in the Burkhart and ElAttrache systems iseliminated along with its associated suture or graft spin.

The system and method of the instant invention provide a simplificationover other currently available anchoring methods and hardware in thatfewer steps are required and moreover the anchor has a simple,single-piece construction. The anchor system is scalable and, due to itssimple construction, may be used with anchors smaller than thosepermitted using other currently available systems. The composition andconstruction in the anchor may be readily modified simply by changingthe material from which it is constructed, by increasing or reducing thediameter or length of the anchor, by increasing or decreasing the wallthickness of the anchor, by modifying the profile of the exterior, or byany combination of these means. All such modifications are contemplatedas within the scope of the present invention.

In another aspect, the present invention provides a method for affixinga soft tissue graft to a target boney surface, the method comprising thesteps of:

-   -   a. providing a placement system having an optionally cannulated        non-rotating tensioning device (“inner assembly”) and a        cannulated driver device (“outer assembly”), wherein the        tensioning device is positioned within the cannulation or        “lumen” of the driver device,    -   b. positioning a cannulated anchor onto the distal        torque-transmitting portion of the driver, over a distally        extending element of the tensioning device,    -   c. producing a suitably configured hole (i.e., “socket”) in a        prepared boney surface at a desired target location using a        drill, tap, punch or equivalent hole-producing device,    -   d. drawing sutures from the graft into the lumen of the        tensioning device,    -   e. inserting the distal end of the tensioning device into the        socket,    -   f. applying tension to the sutures to draw the graft to a        desired position,    -   g. placing the anchor (or interference screw) in the socket,    -   h. withdrawing the placement system,    -   i. trimming the suture tails, and    -   j. optionally repeating steps (c) through (i) as required.

In an alternate embodiment of the present invention, identical in allaspects to the previous embodiment except as subsequently described, thetubular distal portion of the tensioning device is replaced by a rodhaving formed at its distal end a sharpened fork portion. Two (or more)parallel, axially extending tines form the fork, the tines being spacedapart so that sutures may slide freely through the channel(s) formedbetween the tines. An anchor placement system commensurate with such anembodiment is used in the following manner: First, a cannulated threadedimplant is removably mounted to the torque-transmitting distal portionof the driver. Sutures placed in the graft are then positioned in thechannel(s) of the distal fork portion of the tensioning device. Theelongate distal portion of the tensioning device with the suturespositioned within its distal channel is then inserted into a preparedsocket so that the distal end of the tensioning device with its suturesis positioned at the bottom of the socket. Tension is then applied tothe sutures by pulling on their proximal ends to draw the graft into thedesired position. The desired tension and graft position may bemaintained by cleating the suture proximal portions in slots optionallyformed in the handle of the tensioning device. The anchor is thenscrewed, threaded or otherwise driven into the socket by the driver,thereby trapping the sutures or graft between the anchor exteriorsurface and the socket wall. Twisting of the sutures or graft isprevented by the non-rotating distal fork portion of the tensioningdevice, which remains distal to the anchor distal end during anchorplacement. The tension on the sutures and the position of the graft aremaintained during placement of the anchor. After anchor placement, thedriver and tensioning device are removed from the site and the suturestrimmed to complete the procedure.

A further aspect of the instant invention addresses the placement ofsmall diameter implants. In particular, the placement of small diameterimplants using a cannulated tensioning device such as presentlydescribed may be problematic since the cannulation in the implantdecreases with the implant diameter. This decrease in the implantcannulation diameter necessitates a corresponding decrease in thecannulation diameter of the tensioning device distal portion. As aresult, the diameter of the cannulation in the tensioning device distalportion may potentially be insufficient to accommodate the number andsize of sutures required for the proper securing of an associated graft.Accordingly, in yet another embodiment of the present invention for usepredominantly with small diameter implants, an elongate element formedfrom a suitable metallic or polymeric material forms a retention loopdistal to the distal end of the distal portion of the cannulatedtensioning device, with the proximal ends of the elongate elementextending to the proximal end of the tensioning device where they areremovably secured. One or more sutures are loaded into the distalretention loop formed by the elongate element. Thereafter, tensioning ofthe sutures and placement of the implant are as previously hereindescribed, for example following the steps utilized in connection withthe previously described tensioning device including a “forked” distalend. After the implant is properly placed, the proximal ends of theelongate element are freed and the elongate element is removed from thesite by withdrawing of the proximal ends. In a preferred embodiment, theelongate element is formed of a nitinol wire.

Yet another aspect of the instant invention addresses the constructionof small diameter implants. The minimum size of threaded metal anchorsthat may be created and their configurations are limited by the abilityof a machine tool to produce them. The configurations of small metalanchors used in, for instance, hand surgery are limited to those thatrequire the tying of knots after passing suture through a graft.Similarly, threaded anchors made of polymeric materials such as PEEK arelimited in their minimum size by the strength of the underlyingmaterial. When these threaded anchors become very small, the ability ofa driver to transmit torque to the implant is limited by the resistanceto deformation of the torque-transmitting features of the implant. Whenconventional (i.e., not knotless) anchors are used, the graft must besecured in position by tying knots on the surface of the graft oppositethe attachment site. These knots are frequently perceptible beneath theskin of the patient and can create irritation for the patient.Accordingly, there is a need for very small knotless anchors configuredfor small joint repairs.

In the course of the present invention, it was discovered that anchorsystems of the present invention that use an elongate wire element asdescribed above may be miniaturized through the use of advancedmaterials having high tensile strengths along with the use of advancedmanufacturing techniques. Specifically, very small knotless anchors maybe produced from ceramic materials using a process known as “CeramicInjection Molding” or simply “CIM”. The tensile strength of PEEKmaterial is typically between 10,000 and 15,000 psi. In comparison, thetensile strength of alumina is generally in excess of 200,000 psi.Furthermore, recently developed materials such as Zirconia ToughenedAlumina (ZTA) by Coorstek Inc. (Golden, Colo.) have a high degree oftoughness in addition to high tensile strength. These materials, beingceramic, do not have a yield point and therefore do not deform underload. The high tensile strength and the absence of yielding under loadof an implant constructed of such ceramic materials allow torque to betransmitted to the implant through features that are not producible bythe machining of metal or that would fail in use if formed from apolymeric material such as PEEK. Thus, ceramic knotless anchors of thepresent invention may be produced in sizes and configurations notpossible using prior art technology.

Accordingly, in certain embodiments of the present invention, the distaltorque-transmitting portion of the driver may also be ceramic, formed byceramic injection molding so as to allow miniaturization of thetorque-transmitting features. In other embodiments, thetorque-transmitting portion of the implant is a laterally extending slotin the proximal end of the implant similar to a standard screwdriverslot, wherein the ceramic material from which the implant is formed issufficient to ensure that the anchor does not fail by fracture proximalto its distal end or by failure of the torque-transmitting proximalslot. In yet other embodiments, the ceramic implant is an interferenceplug, wherein the high elastic modulus and high strength of the ceramicmaterials is beneficial for small and miniature interference typeanchors that are driven axially into a prepared socket. The high modulusand high strength of the materials allows the thickness of the wallbetween the central lumen and the outer surface to be reduced comparedto interference type anchors produced from polymeric materials withoutreducing the compressive force which retains the one or more suturesbetween the outer wall of the implant and the wall of the socket.

As an improvement over the prior art, threaded implants placed using thesystems of the present invention may be readily removed after placement.If the initial tensioning of a suture affixed in a prepared socket usinga threaded implant and system of the present invention is determined bythe surgeon to be suboptimal, the implant may be backed out of thesocket using the same system used for its placement. The suture may thenbe re-tensioned and secured using the same implant that was removed. If.after placement and tensioning of a suture. the anchor position is foundto be sub-optimal, the implant may be backed out of the socket in thesame manner, after which a new socket may formed in an alternatelocation, and the suture may tensioned and retained in the new socketusing the same implant removed from the original socket.

Another aspects of the anchor placement system of the present inventionrelates to the inclusion of a mechanism for releasably preventingrelative axial and rotational movement between the driver and thetensioning device, such means optionally positioned within thecannulation (or “lumen”) of the driver. In a first condition used duringtensioning of the suture, relative axial and rotational motion of thedriver relative to the tensioning device is prevented. In a secondcondition, used during placement of the anchor, the driver may beadvanced axially on the tensioning device to bring the anchor to thesocket, and rotated to screw the anchor into the socket, with thetensioning device remaining stationery so as to maintain suture tensionand prevent twisting of the sutures.

In a particularly preferred embodiment, prevention of relative motion isprovided by a removable key having one or more protrusions, coupled withfeatures formed on the handles of the tensioning device and driver suchthat, when the features are in alignment, engagement by the one or moreprotrusions of the key prevents relative axial or rotational movementbetween the torque-transmitting driver and the tensioning device.Removal of the key allows the driver to be advanced distally and rotatedrelative to the tensioning device. Other embodiments are anticipated inwhich other means are used to releasably prevent relative motion.

In yet another aspect, like the previous in all other respects except assubsequently described, the suture attached to the graft is positionedwithin the distal fork and tensioned such that the proximal end of thegraft is adjacent to the fork, the tension being maintained by cleatingof the sutures on the tensioning device handle. The distal portion ofthe tensioning device with the graft is inserted into the preparedsocket. The anchor is then threaded or driven into the socket aspreviously described, thereby trapping the graft proximal portionbetween the anchor exterior surface and a first portion of the socketwall, and the attached sutures between the anchor exterior surface and asecond, laterally opposed portion of the socket wall. In a variation ofthe previous aspect, the graft may be pierced by the sharpened, distallyextending members (“tines”) of the distal fork. The distal portion ofthe tensioning element with the graft is inserted into the preparedsocket. Once again, the anchor is then threaded or driven into thesocket, thereby trapping the graft proximal portion between the anchorexterior surface and a portion of the socket wall.

In another variation of the previous aspect, the graft is pierced by thesharpened distally extending members of the distal fork a predetermineddistance from the graft distal end such that when the distal portion ofthe tensioning element with the graft is inserted into the preparedsocket, the proximal end of the graft protrudes above the opening of thesocket. The anchor is then threaded or driven into the socket, therebytrapping the graft proximal portion between the anchor exterior surfaceand first and second laterally opposed portions of the socket wall.

In still yet another aspect, identical in form to the devices andinsertion systems previously herein described, the tensioning device hasa proximal handle portion that is an assembly of first and second rigidelements with an elastic element positioned therebetween. Applying adistal force to a first rigid element of the handle of the tensioningdevice causes deflection of the elastic element proportional to thetension in the graft attached to the distal fork. This allows thepractitioner to measure the tension in the graft. By establishing thetension in the graft to a predetermined value prior to placement of theanchor, the tension may then be maintained at the predetermined valueduring anchor placement.

Another aspect of the present invention relates to the use of a familyof knotless anchor placement systems in accordance with the presentinvention to allow tensioning of a suture prior to placement of animplant. The tension in the suture may be readjusted by removing theimplant, adjusting the tension and resetting the implant in the sameprepared socket. In a first embodiment, the system draws sutures intothe central lumen of a non-rotating tensioning device located within thecannulation of a driver device, such that the tension on the sutures mayestablished by pulling on the suture portions proximal to the insertiondevice handle. After satisfactory tension is achieved and maintained bycleating to the insertion device handle, an implant is threaded into thesocket. The system is described in U.S. Pat. No. 9,226,817, the contentsof which are hereby included by reference in their entirety.

A second system is like the first in that a non-rotating tensioningdevice is positioned within the cannulation of a driver device. However,unlike the first system, the tensioning device is not cannulated and thedistal end of the tensioning device has formed thereon a “fork” such asdescribed above, wherein sutures may be retained in the fork fortensioning prior to anchor placement. This system is described in U.S.Pat. No. 9,226,817, the contents of which are hereby included byreference in their entirety.

A third system is alike in form to the first system except that insteadof drawing sutures into the central lumen of the non-rotating tensioningdevice, a suture retention loop is formed distal to the distal end ofthe insertion device by an elongate wire that extends to the proximalend of the insertion device. Sutures are loaded into this wire loop andmaintained in position at the distal end of the insertion device therebyduring tensioning of the sutures and anchor placement. Thereafter theelongate wire is removed. Details of the system are contained in arelated co-pending application entitled “Ceramic Implant PlacementSystems And Superelastic Suture Retention Loops For Use Therewith” Ser.No. 15/256,815 filed contemporaneously with the instant application, thecontents of which are herein incorporated by reference in theirentirety. The unique ability of these systems to establish tension in asuture prior to lateral anchor placement, and their ability to allow animplant to be removed and reinserted by the surgeon if modification ofthe tension is necessary, enable simplified methods for multi-anchorreattachment of soft tissue grafts to bone. Unlike prior art methodsthat utilize two-piece anchor systems (e.g., a suture retaining eyeletand a proximal interference screw or plug as in Burkhart, or an anchorand a suture securing “anchor top” as described by Green et al.),tensioning is accomplished prior to the placement of any implant. Inaddition, unlike prior art methods, the suture may be removably affixedby the lateral implant, with a lateral portion of the suture beingtrapped between at least a first portion of the implant outer surfaceand the wall of the socket in which it is placed. This stands in starkcontrast to procedures and protocols outlined in the prior art,including the method of Green et al., wherein in the suture is fixedlysecured to the second (lateral) anchor. Thus, the system and method ofthe present invention serves to reduce the number of steps that thesurgeon must perform, thereby resulting in time and cost savings, and areduction in the opportunity for error. To wit, if an error occurs,methods and devices of the present invention permit the easy removal ofthe single-piece implant for retensioning of the suture and reinsertionof the implant, or the relocation of the same implant if the originallocation is determined to be unsuitable.

Accordingly, in a preferred aspect, the present invention provides amethod for affixing a soft tissue graft to a target boney surface, themethod including the steps of:

a. affixing at least one suture to the bone medial to the lateral edgeof the soft tissue by means of a first implant, such as cannulatedknotless suture anchor, such that no portion of the implant lies lateralto the soft tissue edge;

b. passing a first length of suture from the first implant over the softtissue;

c. forming a socket lateral to the edge of the soft tissue such that itis not underneath the soft tissue;

d. establishing a desired tension in the first length of suture; and

e. placing the first implant in the socket so as to trap a portion ofthe first length of suture between at least a first portion of theimplant and the wall of the socket so as to provide fixation.

In certain preferred embodiments, the lateral implant may be threaded soas to provide removable fixation to the suture. In such embodiments withremovable fixation of the suture, the method of the present inventionmay also optionally include the following additional steps:

f. removing the lateral implant from the socket in which it was placed;

g. adjusting the tension in the first length of suture; and

h. placing the same implant in the socket so as to trap a portion of thefirst length of suture between at least a first portion of the implantand the wall of the socket so as to provide removable fixation.

Alternatively, in another preferred embodiment, the following optionalsteps may be included:

f. removing the lateral implant from the socket in which it was placed;

g. forming a socket in a new location lateral to the edge of the softtissue such that it is not underneath the soft tissue;

h. establishing a desired tension in the first length of suture; and

i. placing the same implant in the socket so as to trap a portion of thefirst length of suture between at least a first portion of the implantand the wall of the socket so as to provide removable fixation.

Double row repairs of large rotator cuff tears may require constructs inwhich a matrix of medial and lateral implants are used. Sutures may spanthe tissue between a row of medial implants and a row of lateralimplants so as to ensure reliable contact between the soft tissue andunderlying bone in the region between the rows of implants. For example,an implant in the medial row may anchor multiple sutures that extend tomultiple lateral implants as well as to adjacent medial row implants. Inmethods of the current invention, each tissue-spanning suture extendingfrom a first medial anchor may be individually tensioned prior to beingremovably affixed to the bone by a second implant. If the tension in anysuture of the construct is found to be unsuitable, the tension may beadjusted using methods previously herein described. Likewise, if thelocation of any anchor of a construct is found to be unsuitable, theimplant may be relocated using methods previously herein described.Alternatively or additionally, if upon completion of forming a doublerow construct, the surgeon finds that a region of the rotator cuff isnot securely compressed against the underlying bone (a conditionreferred to by surgeons as a “dog ear”) one or more additional implantsmay be placed so as to span the region with tensioned sutures. Suturesfrom the supplemental implant(s) may be integrated into the previouslyformed construct by removing one or more implants of the construct,adding the spanning sutures from the supplemental implants, andtensioning and securing the sutures as previously herein described.

These and other aspects are accomplished in the invention hereindescribed, directed to a system and method for producing a matrix ofimplants for the anchoring of a graft to bone. Further objects andfeatures of the invention will become more fully apparent when thefollowing detailed description is read in conjunction with theaccompanying figures and examples. For example, because the implantsystems and methods of the present invention provide removable fixationof the sutures to the underlying bone, numerous modifications may bemade to the completed construct, or the construct may even be removed inits entirety. However, it is to be understood that both the foregoingsummary of the invention and the following detailed description are of apreferred embodiment, and not restrictive of the invention or otheralternate embodiments of the invention. In particular, while theinvention is described herein with reference to a number of specificembodiments, it will be appreciated that the description is illustrativeof the invention and is not constructed as limiting of the invention.

BRIEF DESCRIPTION OF THE FIGURES

Various aspects and applications of the present invention will becomeapparent to the skilled artisan upon consideration of the briefdescription of figures and the detailed description of the presentinvention and its preferred embodiments that follows:

FIG. 1 is a perspective view of an exploded assembly of a first anchorplacement system of the present invention.

FIG. 2 is a plan view of the assembled system of FIG. 1.

FIG. 3 is an expanded plan view of the elements of FIG. 2 at location A.

FIG. 4 is an expanded sectional view of the objects of FIG. 2 atlocation A-A.

FIG. 5 is a side elevational view of the objects of FIG. 2.

FIG. 6 is an expanded view of the objects of FIG. 5 at location B.

FIG. 7 is a perspective view of the objects of FIG. 2.

FIG. 8 is an expanded view of the objects of FIG. 7 at location C.

FIG. 9 is a perspective view of an exploded assembly of a second anchorplacement system of the present invention.

FIG. 10 is a side elevational view of the objects of FIG. 9.

FIG. 11 is a proximal axial view of the objects of FIG. 9.

FIG. 12 is an expanded view of the distal portion of the objects of FIG.9.

FIG. 13 is a plan view of the objects of FIG. 12.

FIG. 14 is a sectional view of the objects of FIG. 12 at location B-B.

FIG. 15 is a distal perspective view of the objects of FIG. 9.

FIG. 16 is an expanded view of the objects of FIG. 15 at location A.

FIG. 17 is a proximal perspective view of the objects of FIG. 9.

FIG. 18 is an expanded view of the objects of FIG. 17 at location B.

FIG. 19 is a perspective view of an exploded assembly of a third anchorplacement system of the present invention.

FIG. 20 is a perspective view of the assembled anchor placement systemof FIG. 19.

FIG. 21 is an expanded distal perspective view of the distal portion ofthe anchor placement system of FIG. 20.

FIG. 22 is an expanded proximal perspective view of the distal portionof the anchor placement system of FIG. 20.

FIG. 23 is an expanded proximal perspective view of the proximal portionof the anchor placement system of FIG. 20.

FIG. 24 is an expanded distal perspective view of the proximal portionof the anchor placement system of FIG. 20

FIG. 25 is a perspective view of the anchor placement system of FIG. 20with suture loaded in preparation for use.

FIG. 26 is an expanded view of the distal portion of the anchorplacement system of FIG. 25.

FIG. 27 is a diagrammatic representation of a graft and bone from whichthe graft has been separated as in a rotator cuff tear.

FIG. 28 depicts the graft and bone of FIG. 27 with a first medial socketsuitable for the placement of an anchor formed in the bone.

FIG. 29 depicts the graft and bone of FIG. 28 with the distal portion ofthe anchor placement system of FIG. 19 inserted into the first medialsocket in preparation for the placement of a first tissue anchor.

FIG. 30 depicts the elements of FIG. 29 wherein a first anchor has beenplaced in the first medial socket so as to affix a suture thereto.

FIG. 31 depicts a suture affixed to the bone by a first anchor placed ina first socket.

FIG. 32 depicts the objects of FIG. 31 wherein a second lateral socketsuitable for placement of an anchor therein has been formed in the bone.

FIG. 33 is a proximal perspective view of the anchor placement system ofFIG. 19 wherein the suture previously affixed to the bone by the firstmedial anchor is prepared for loading into the anchor placement system.

FIG. 34 is a proximal perspective view of the objects of FIG. 33 whereinthe suture is loaded into the suture placement system.

FIG. 35 depicts the elements of FIG. 32 wherein the distal portion ofthe first anchor placement system of FIG. 2 is inserted into the secondlateral socket in preparation for tensioning of the suture for anchorplacement.

FIG. 36 depicts the objects of FIG. 35 wherein the suture has beentensioned in preparation for anchor placement.

FIG. 37 depicts the objects of FIG. 36 wherein the anchor has beenplaced in the second lateral socket so as to affix the suture to thebone.

FIG. 38 depicts a completed construction in which a portion of a graftis retained against a boney surface by a tensioned suture extendingbetween a first medial anchor and a second lateral anchor in accordancewith the principles of the present invention.

FIG. 39 depicts a medial anchor affixing two sutures to a bone forsecuring a graft to a prepared boney surface.

FIG. 40 depicts the completed construction of FIG. 38 with additionalsutures secured by the medial and lateral anchors.

FIG. 41 is a perspective view of a placed first medial implant of adouble row construct for rotator cuff reattachment according to themethods of the present invention.

FIG. 42 is a perspective view of the first and second medial implants ofa double row fixation with a tensioned suture joining the implants.

FIG. 43 is a perspective view of the medial implants of FIG. 42 and afirst lateral implant placed with tensioned sutures joining the medialimplants to the first lateral implant.

FIG. 44 is a perspective view of the elements of FIG. 43 with a secondlateral implant placed and joined to the medial implants by tensionedsutures.

FIG. 45 is a perspective depiction of a completed double row repairusing the elements of FIG. 44.

FIG. 46 is a perspective view of a double row construct of the presentinvention in which a lateral implant has been removed in preparation forrepositioning the implant.

FIG. 47 is a perspective view of the elements of FIG. 46 with theaddition of a socket formed in a new location.

FIG. 48 is a perspective view of the elements of FIG. 47 wherein thelateral implant is placed in the socket formed in the new location andtensioned sutures connect to the medial implants.

FIG. 49 is a perspective view of the modified double row construct ofFIGS. 46 and 47.

FIG. 50 depicts a double row construct of the present invention having aregion adjacent to the construct in which a lateral region of the softtissue is not in contact with the underlying bone.

FIG. 51 is a perspective view of the distal portion of an alternateembodiment implant placement system configured for the placement ofsmall preferably ceramic implants.

FIG. 52 is a side elevational view of the objects of FIG. 51.

FIG. 53 depicts the objects of FIG. 50 wherein a lateral implantadjacent to the lateral region of non-contacting soft tissue is removedand a small diameter socket has been formed in proximity to thenon-contacting tissue region, lateral to the edge of the soft tissue.

FIG. 54 depicts the objects of FIG. 54 wherein the lateral anchor whichwas removed is again placed in its original socket and a small anchor ofthe implant system of FIG. 51 is placed in the adjoining small diametersocket, with tensioned sutures spanning the soft tissue.

FIG. 55 depicts the completed construct of FIG. 54.

FIG. 56 depicts another repair construct in which a region ofnon-contacting soft tissue adjacent to the original double row constructis pressed against the underlying bone by sutures tensioned betweensmall diameter anchors placed adjacent to the original construct.

FIG. 57 depicts a perspective view the distal portion of an alternateembodiment implant placement system for use with small push-in plug-typeimplants.

FIG. 58 is a side elevational view of the objects of FIG. 57.

FIG. 59 depicts a two-implant repair in which the lateral anchor is asmall push-in plug-type implant, the construct being formed usingmethods of the present invention.

FIG. 60 depicts a double-row repair construct in which the lateralanchors are small push-in plug-type implants, the construct being formedusing methods of the present invention.

FIG. 61 depicts a repair construct with two medial implants and a singlelateral implant wherein the anchors are small push-in implants, theconstruct being formed using methods of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Aspects of the present invention relate to and/or overlap with aspectsdescribed in related co-pending and contemporaneously filed applicationsentitled “Ceramic Implant Placement Systems And Superelastic SutureRetention Loops For Use Therewith” Ser. No. 15/256,815 and “ImplantPlacement Systems And One-Handed Methods For Tissue Fixation Using Same”Ser. No. 15/256,838, the entire contents of which are herebyincorporated in their entirety.

Although any methods and materials similar or equivalent to thosedescribed herein can be used in the practice or testing of embodimentsof the present invention, the preferred methods, devices, and materialsare now described. However, before the present materials and methods aredescribed, it is to be understood that the present invention is notlimited to the particular sizes, shapes, dimensions, materials,methodologies, protocols, etc. described herein, as these may vary inaccordance with routine experimentation and optimization. It is also tobe understood that the terminology used in the description is for thepurpose of describing the particular versions or embodiments only, andis not intended to limit the scope of the present invention which willbe limited only by the appended claims. Accordingly, unless otherwisedefined, all technical and scientific terms used herein have the samemeaning as commonly understood by one of ordinary skill in the art towhich the present invention belongs. However, in case of conflict, thepresent specification, including definitions below, will control.

In the context of the present invention, the following definitionsapply:

The words “a”, “an” and “the” as used herein mean “at least one” unlessotherwise specifically indicated. Thus, for example, reference to an“opening” is a reference to one or more openings and equivalents thereofknown to those skilled in the art, and so forth.

The term “proximal” as used herein refers to that end or portion whichis situated closest to the user of the device, farthest away from thetarget surgical site. In the context of the present invention, theproximal end of the implant system of the present invention includes thedriver and handle portions.

The term “distal” as used herein refers to that end or portion situatedfarthest away from the user of the device, closest to the targetsurgical site. In the context of the present invention, the distal endof the implant systems of the present invention includes componentsadapted to fit within the pre-formed implant-receiving socket.

In the context of the present invention, the terms “cannula” and“cannulated” are used to generically refer to the family of rigid orflexible, typically elongate lumened surgical instruments thatfacilitate access across tissue to an internally located surgery site.

The terms “tube” and “tubular” are interchangeably used herein to referto a generally round, long, hollow component having at least one centralopening often referred to as a “lumen”.

The terms “lengthwise” and “axial” as used interchangeably herein torefer to the direction relating to or parallel with the longitudinalaxis of a device. The term “transverse” as used herein refers to thedirection lying or extending across or perpendicular to the longitudinalaxis of a device.

The term “lateral” pertains to the side and, as used herein, refers tomotion, movement, or materials that are situated at, proceeding from, ordirected to a side of a device.

The term “medial” pertains to the middle, and as used herein, refers tomotion, movement or materials that are situated in the middle, inparticular situated near the median plane or the midline of the deviceor subset component thereof.

As discussed above, when a tissue, more particularly a soft connectivetissue in a joint space, becomes damaged or torn from its associatedbone or cartilage, surgery is usually required to reattach the tissue orreconstruct the bone. The present invention is directed to various meansand mechanisms for securing the displaced tissue to boney tissue.

As used herein, the term “tissue” refers to biological tissues,generally defined as a collection of interconnected cells that perform asimilar function within an organism. Four basic types of tissue arefound in the bodies of all animals, including the human body and lowermulticellular organisms such as insects, including epithelium,connective tissue, muscle tissue, and nervous tissue. These tissues makeup all the organs, structures and other body contents. While the presentinvention is not restricted to any particular soft tissue, aspects ofthe present invention find particular utility in the repair ofconnective tissues such as ligaments or tendons, particularly those ofthe shoulder, elbow, knee or ankle joint.

In a similar fashion, while the present invention is not restricted toany particular boney tissue, a term used herein to refer to both bonesand cartilage, aspects of the present invention find particular utilityin the repair or reattachment of connective tissues to the boneyelements of the shoulder, elbow, knee or ankle joint.

When the damaged tissue is of sufficient quantity and quality, thedamaged portion may simply be directly reattached to the bone from whichit was torn so that healing back to the bone can take place. However, inother situations, a “graft” may be needed to stimulate regrowth andpermanent attachment. In the context of the present invention, the term“graft” refers to any biological or artificial tissue being attached tothe boney tissue of interest, including:

-   -   Autografts, i.e., grafts taken from one part of the body of an        individual and transplanted onto another site in the same        individual, e.g., ligament graft;    -   Isografts, i.e., grafts taken from one individual and placed on        another individual of the same genetic constitution, e.g.,        grafts between identical twins;    -   Allografts, i.e., grafts taken from one individual placed on        genetically non-identical member of the same species; and    -   Xenografts, i.e., grafts taken from one individual placed on an        individual belonging to another species, e.g., animal to man.        Autografts and isografts are usually not considered as foreign        and, therefore, do not elicit rejection. Allografts and        xenografts are recognized as foreign by the recipient thus carry        a high risk of rejection. For this reason, autographs and        isografts are most preferred in the context of the present        invention.

Surgical interventions such as contemplated herein generally require theboney tissue to be prepared for receiving the graft. In the context ofthe present invention, such preparation includes the formation of a“socket”, i.e., a hole punched or drilled into the bone into which aprosthetic device such as an implant may be received. The socket may beprepared at the desired target location using conventional instrumentssuch as drills, taps, punches or equivalent hole-producing devices.

While certain procedures contemplate directly attaching the graft to thebone, the more common route involves the employment of an implantspecially configured to hold and/or enable attachment of the graft tothe boney tissue. As used herein, the term “implant” refers to aprosthetic device fabricated from a biocompatible and/or inert material.In the context of the present invention, examples of such “implants”include conventional and knotless anchors of both the screw-threaded andinterference-fit variety, as well as interference screws.

In certain embodiments, the present invention contemplates fabricationof the implant from either a metallic material or a suitable polymericmaterial, including, but not limited to, polyetheretherketone (PEEK), apolymeric composite such as, for instance, carbon fiber reinforced PEEK(PEEK CF), or of a suitable bioabsorbable material such as, forinstance, polylactic acid (PLA). The present invention also contemplatesthe use of very small knotless anchors produced from ceramic materialsusing a process known as “Ceramic Injection Molding” or simply “CIM”.The tensile strength of PEEK material is typically between 10,000 and15,000 psi. In comparison, the tensile strength of alumina is generallyin excess of 200,000 psi. Furthermore, recently developed materials suchas Zirconia Toughened Alumina (ZTA) by Coorstek Inc. (Golden, Colo.)have a high degree of toughness in addition to high tensile strength.These materials, being ceramic, do not have a yield point and thereforedo not deform under load. The high tensile strength and the absence ofyielding under load of an implant constructed of such ceramic materialsallow torque to be transmitted to the implant through features that arenot producible by the machining of metal or that would fail in use ifformed from a polymeric material such as PEEK.

In certain embodiments, the implant may take the form of a ceramicinterference plug, wherein the high elastic modulus and high strength ofthe ceramic materials is beneficial for small and miniature interferencetype anchors that are driven axially into a prepared socket. The highmodulus and high strength of the materials allows the thickness of thewall between the central lumen and the outer surface to be reducedcompared to interference type anchors produced from polymeric materialswithout reducing the compressive force which retains the one or moresutures between the outer wall of the implant and the wall of thesocket.

The preferred implant system of the present invention is comprised of anoptionally cannulated tensioning device (also referred to as the“inserter” or “insertion device”) slidably received within the lumen ofa cannulated driver device (also referred to as the implant driver) thattogether serve to tension sutures in a prepared socket for the placementof a simple one-piece cannulated anchor. In the Examples below, thepresent invention makes reference to various lock-and-key type matingmechanisms that serve to establish and secure the axial and rotationalarrangement of these device components. It will again be readilyunderstood by the skilled artisan that the position of the respectivecoordinating elements (e.g., recessed slots and grooves that mate withassorted projecting protrusions, protuberances, tabs and splines) may beexchanged and/or reversed as needed.

The implant placement system of the present invention requires a robustconnection between the “driver device” and the associated “implant” or“anchor” so as to ensure that the two rotate as a single unit such thatrotational force or “torque” applied to the proximal end of the system(e.g., via the proximal handle portion of the driver device) istransmitted to the distal end of the system (e.g., the distal end of theimplant disposed in the prepared socket) without incident orinterruption. This continuous “torque transfer” along the length of thesystem, from proximal to distal end, is critical to the function of thedriver, enabling it to distally advance the implant and firmly securethe implant (and any associated sutures or tissues) in the biologicalsite of interest. In the context of the present invention, thiscontinuous torque transfer is achieved by means of coordinating“torque-transmitting” elements, namely a distal “torque-transmittingportion” of the driver device that is configured to mate with and/orconform to a “torque-transmitting” (or alternatively “torque-receiving”or “torque-transferring”) portion of the implant, such “portion”including at a minimum the proximal end of the implant though thepresent invention contemplates embodiments where “torque-transmitting”features on the implant extend along the length of the implant. Therespective “torque-transmitting” features on the driver device andimplant cooperate to ensure that any proximal torque applied by the userto the proximal handle portion of the device is directly conveyed(“transmitted”) to the distal end of the implant.

In certain embodiments, the torque-transmitting portion of the implantmay take the form of a laterally extending slot in the proximal end ofthe implant similar to a standard screwdriver slot; however, othergeometries are contemplated and described in detail herein as well as indisclosures incorporated by reference herein. In addition, like theimplant itself, the distal torque-transmitting portion of the driver mayalso be fabricated from a ceramic material and formed by ceramicinjection molding so as to allow miniaturization of thetorque-transmitting features.

The present invention makes reference to insertion devices commonlyreferred to in the art as “drills” and “drivers”, i.e., devices that“drill” the socket and “drive” the implant into the socket. In thecontext of the present invention, the drills and drivers may beconventional, e.g., rigidly linear as previously herein described, or,as discussed in detail herein, “off-axis”, e.g., having an angularlyoffset distal portion adapted to drill off-axis sockets in boney tissuesthat are remote and difficult to access and drive therein thecorresponding implant, such as an anchor or interference screw.

The present invention contemplates securing the graft to the implant viasutures. In the context of the present invention, the term “suture”refers to a thread-like strand or fiber used to hold body tissues aftersurgery. Sutures of different shapes, sizes, and thread materials areknown in the art and the present invention is not restricted to anyparticular suture type. Accordingly, in the context of the presentinvention, the suture may be natural or synthetic, monofilament ormultifilament, braided or woven, permanent or resorbable, withoutdeparting from the spirit of the invention.

In certain embodiments, the present invention makes reference to anelongate element of a superelastic and/or shape memory materialconfigured to include a suture retention loop at its distal end anddesigned to be slidably received within a lumen of a cannulatedtensioning device or inserter. In certain preferred examples, theelongate element takes the form of a “nitinol wire”. In the context ofthe present invention, “nitinol” is a super elastic metal alloy ofnickel and titanium. In a preferred embodiment, the two elements arepresent in roughly equal atomic percentage (e.g., Nitinol 55, Nitinol60). Nitinol alloys exhibit two closely related and unique properties:shape memory effect (SME) and superelasticity (SE; also calledpseudoelasticity, PE). Shape memory is the ability of nitinol to undergodeformation at one temperature, then recover its original, undeformedshape upon heating above its “transformation temperature”.Superelasticity occurs at a narrow temperature range just above itstransformation temperature; in this case, no heating is necessary tocause the undeformed shape to recover, and the material exhibitsenormous elasticity, some 10-30 times that of ordinary metal.

The present invention also makes reference to high strength polymericmaterials and high tensile strength ceramic materials, such as aluminaor zirconia, that may be formed to complex shapes by a process referredto as Ceramic Injection Molding (CIM). In this process, ceramic powderand a binder material are molded to a shape that is subsequently firedin a furnace to eliminate the binder material and sinter the ceramicpowder. During this sintering operation the item is reduced in size bytwenty to thirty percent and achieves near 100% density with very highdimensional repeatability. Ceramic materials that are routinely moldedand thus contemplated by the present invention include, but are notlimited to, alumina, zirconia toughened alumina (ZTA) and partiallystabilized zirconia (PSZ). The flexular strengths of these materialsrange from 55,000 psi to 250,000 psi, far higher than the 25,000 psiflexular strength of implantable PEEK material.

The instant invention has both human medical and veterinaryapplications. Accordingly, the terms “subject” and “patient” are usedinterchangeably herein to refer to the person or animal being treated orexamined. Exemplary animals include house pets, farm animals, and zooanimals. In a preferred embodiment, the subject is a mammal, morepreferably a human.

Hereinafter, the present invention is described in more detail byreference to the Figures and Examples. However, the following materials,methods, figures, and examples only illustrate aspects of the inventionand are in no way intended to limit the scope of the present invention.For example, while the present invention makes specific reference toarthroscopic procedures, it is readily apparent that the teachings ofthe present invention may be applied to other minimally invasiveprocedures and are not limited to arthroscopic uses alone. As such,methods and materials similar or equivalent to those described hereincan be used in the practice or testing of the present invention.

EXAMPLES

FIG. 1 depicts driver 1500 with anchor 1600 loaded thereto, tensioning(insertion) device 1400 with loading loop 1300 positioned for loading asuture, and key 1200 prior to mounting of driver 1500 to tensioningdevice 1400 in preparation for use. When driver 1500 is mounted totensioning device 1400, off-axis slots 1406 of handle 1402 of tensioningdevice 1400 are aligned with off-axis holes 1506 of handle 1502 ofdriver 1500 and cylindrical portions of key 1200 are inserted into thepassages so formed. Positioning of key 1200 in this manner preventsaxial and rotational movement of tensioning device 1400 relative todriver 1500. FIGS. 2 through 8 depict knotless suture anchor system 1000of the instant invention prepared for use with key 1200 and loading loop1300 in place. Distal tubular element 1412 of tensioning device 1400extends distally beyond anchor 1600 and distal driving element 1512 ofdriver 1500. Detailed descriptions of the construction and use ofplacement system 1000 are contained in U.S. Pat. No. 9,226,817 thecontents of which are incorporated herein by reference in theirentirety.

FIGS. 9 through 18 depict a second implant placement system 2000 of thepresent invention having construction like that of placement system1000. That is, non-rotating tensioning device 2400 located within thecannulation of driver 2500 is used to tension one or more sutures priorto the placement of anchor 2600. Placement system 2000 is identical tosystem 1000 in all aspects except as specifically subsequentlydescribed. For example, cannulated distal tubular element 1412 of system1000 may be replaced by distal element 2442 which is not cannulated andhas formed at its distal end elongate laterally opposed, distallyextending portions 2444 with sharpened distal ends 2448. Elongateportions 2444 form the tines of a fork with channel 2446 formed betweenportions 2444. Tensioning device handle 2402 has formed near the distalend of its external surface flanges 2430 wherein are formed slots 2432which serve as cleats for maintaining the tension of sutures placedtherein, flanges 2430 and slots 2432 replacing slots 1408 in hub 1402 ofsystem 1000. The construction and use of placement system 1000 isdescribed in detail in parent application Ser. No. 15/012,060 filed Feb.1, 2016, Ser. No. 14/972,662 filed Dec. 17, 2015, and Ser. No.14/636,389 filed Mar. 3, 2015, the contents of which have beenpreviously incorporated herein by reference in their entirety.

During use, distal element 2412 of tensioning device 2400 is insertedinto a prepared socket in which anchor 2600 is to be placed. Sutures areretained in gap 2446 between distally extending portions 2444 of distalelement 2442 and may be tensioned and cleated in slots 2432 in handle2402 of tensioning device 2400. Thereafter, driver 2500 is uncoupledfrom tensioning device 2400 by the removal of key 2200. Anchor 2600 isthen advanced to the socket and threaded into place while the tensionand graft position are maintained by tensioning device 2400.

Implant placement system 3000, depicted as an exploded assembly oftensioning/insertion device 3400, driver 3500 and anchor 3600 in FIG. 19is configured for the placement of small diameter cannulated implants.The elongate distal portion of tensioning device 3400 is rotatably andslidably positioned within the cannulation of driver 3500. Handles/hubs3402 and 3502 of tensioning device 3400 and 3500 respectively areremovably coupled.

FIGS. 20 through 24 depict implant placement system 3000 assembled andready for use. As shown in FIG. 21, cannulated distal element 3412 oftensioner/inserter 3400 protrudes distally beyond distal drive element3512 and anchor 3600 removably mounted thereon. The distal portion ofelongate element 3900 forms a loop 3902 adjacent to the distal end ofcannulated distal element 3412 of inserter 3400. Second proximal end3904 and first proximal end 3905 of elongate element 3900 are removablysecured (cleated) in slots/cleats 3405, pull-tab 3906 being affixed to afirst end 3905 of elongate element 3900.

An illustrative example of a method for affixing a graft to a boneysurface, as in repairing a torn rotator cuff or other tendon insertiononto a bony surface, is depicted in FIGS. 27 through 38. FIG. 27 depictsa graft 100 that has separated from the surface of bone 200. The regionin which graft 100 is to be reattached to the surface of bone 200 isprepared by abrading with an arthroscopic burr or shaver. Thereafter, asdepicted in FIG. 28, a socket 202 is formed in bone 200 in a selectedlocation beneath cuff 100, forming an opening 102 in graft 100. Suture300 is loaded into the distal loop 3902 of anchor system 3000 asdepicted in FIGS. 25 and 26.

Alternatively, anchor placement systems 1000 or 2000 could besubstituted for system 3000, the choice being one of practionerpreference. Anchor system 3000 is selected for this medial anchorbecause, due to its small diameter, the area for reattachment of graft100 to bone 200 is minimally reduced by socket 202. In this example, asingle suture 300 is used to illustrate the method for placing an anchorand tensioning a suture to affect a rotator cuff repair in accordancewith the principles of the present invention. However, frequently arepair construct employing multiple sutures 300 is needed to secure thegraft to the boney surface. In the context of the present invention,anchor placement system 3000 is able to secure multiple sutures with asmall diameter anchor due to its unique construction and is, therefore,well-suited to placement in locations beneath the soft tissue (medialplacement).

Referring now to FIG. 29, distal element 3412 with loop 3902 of elongateelement 3900 and suture 300 positioned therein (see FIGS. 25 and 26) isinserted into socket 202. Thereafter, as depicted in FIG. 30, anchor3600 is threaded into socket 202 so as to secure suture 300 between thethreaded outer surface of anchor 1600 and the sidewall of socket 200.Elongate element 3900 is then removed and placement system 3000 iswithdrawn from the site. One suture tail may be trimmed as depicted inFIG. 31 or trimmed at the completion of the construct. Socket 204 maythen be formed in bone 200 in a position lateral to cuff 100 as shown inFIG. 32. Suture 300 is then loaded into anchor system 1000 as depictedin FIGS. 33 and 34 using loading loop 1304. Distal element 1412 ofsystem 1000 may be inserted into socket 204 as depicted in FIG. 35 andtensioned as shown in FIG. 36 by pulling on the portion of suture 300proximal to handle 1402 of tensioning device 1400 and cleated in theslots provided so as to maintain the tension. Anchor 1600 may then bescrewed into place thereby trapping suture 300 between the threadedouter surface of anchor 1600 and the wall of socket 204 as shown in FIG.37. Suture 300 is then uncleated from handle 1402 of insertion device1400, placement system 1000 is removed from the site, and suture tail302 is trimmed as shown in FIG. 38. Soft tissue 100 is pressed againstbone 200 by suture 300 extending from medial anchor 3600 to lateralanchor 1600.

In this example, anchor system 1000 was used for the lateral suture.However, anchor placement systems 2000 or 3000 could readily be usedinstead as the choice of a particular system is one of practionerpreference. All of the inventive systems allow the tensioning of suture300 prior to anchor placement. In addition, in contrast to otherknotless anchor systems, if, after anchor placement, the tension insuture 300 is found to be more or less than intended, anchor 1600 (or2600 or 3600) can be backed out, the sutures retensioned, and the anchorthreaded into socket 204 again. This is possible because the anchorsystem uses a single implant to secure the suture by trapping the suturebetween the implant and one or more regions of the socket wall. Thisstands in stark contract to prior art systems that use a first distalimplant secured in place by a second proximal implant in the sameprepared socket, or by an implant to which one or more sutures is fixedsecured by a second, engaging element.

In the example above, a single strand of suture 300 between a singlemedial anchor 3600 and a single lateral anchor 1600 compresses a portionof graft 100 against a prepared surface of bone 200. While this issufficient for very small tears, for larger tears, it is frequentlyadvantageous to retain the graft in its position against the preparedboney surface using a matrix of medial and lateral anchors withtensioned sutures between anchors of the matrix. This method is known asa “double row” technique because it involves a medial “row” of anchorsand a lateral “row” of anchors, the “rows” generally each having two ormore anchors. Tensioning between these adjacent anchors and the fixationof the sutures in the sockets by implants is accomplished in the mannerpreviously herein described. Each implant may affix multiple strands ofsuture; however, in accordance with the principles of the presentinvention, each individual strand of suture may be individuallytensioned and that tension maintained unchanged during placement of theimplant. If required, the tension in each individual strand mayre-adjusted in the manner previously herein described.

FIG. 39 depicts first suture 300 and second suture 304 secured by amedial anchor 3600 in socket 202. The limbs of suture 300 and limbs ofsuture 304 are not trimmed. In FIG. 40, suture 300 has been tensionedand secured by anchor 1600 in the manner previously herein described,but suture limb 302 of suture 300 has not been trimmed. Additionally,third suture 306 is secured by implant 1600. When used in a double rowconstruct of the present invention, a leg of third suture 306 isextended from a second medial row anchor and tensioned prior toplacement of implant 1600.

Hereafter are described methods of the present invention for double rowconstructs for securing soft tissue to an underlying boney surface. Inthe following illustrative examples are depicted methods forconstructing a double row repair, for modifying the tension in one ormore sutures within a double row construct, for repositioning an implantwithin a double row construct, and for adding one or more additionalimplants to a previously formed double row construct.

FIG. 41 depicts a first medial implant 3630 with sutures 300 placed asdepicted in FIG. 39, the first step in forming a double row constructfor the purpose of securing soft tissue 100 to boney surface 200. InFIG. 42, second medial implant 3632 is placed and suture 332 istensioned during placement of implant 3632 as previously hereindescribed. If, following placement of implant 3632 the tension in suture332 is found to be suboptimal, implant 3632 may be backed out and thesuture re-tensioned as previously herein described. Referring now toFIG. 43, subsequently, first lateral implant 1630 is placed as depictedin FIG. 40 and previously herein described. Sutures 334 and 336 aretensioned as previously herein described. If the tension in eithersuture is found to be suboptimal, implant 1630 may be backed out and thetension in each suture leg adjusted as previously herein described.Second medial anchor 1632 is then placed as depicted in FIG. 44 andsutures 338 and 340 tensioned, the tension being subsequently adjustedif required as previously described. With the double row construct nowcompleted, the surgeon may examine the tension of each suture in theconstruct, and if any suture is determined to have suboptimal tension,to adjust the tension in that suture by backing out the appropriateimplant, adjusting the suture tension and then reseating the implant.FIG. 45 depicts the double row construct with the sutures trimmed tocomplete the repair.

Referring again to FIG. 44, if the surgeon determines that the constructis suboptimal and that the repair may be improved by repositioning of animplant, a socket may be formed in the desired implant location.Thereafter the implant to be repositioned is removed from its originalsocket and placed in the newly formed socket using methods previouslyherein described. In FIG. 46, second lateral implant 1632 has beenremoved from socket 204 in which it was previously placed. In FIG. 47socket 206 has been formed in the alternate location, and in FIG. 48implant 1632 has been placed in newly formed socket 206 and sutures 338and 340 tensioned and affixed thereby. FIG. 49 depicts the completedrepair with the suture tails trimmed.

FIG. 50 depicts the construct of FIG. 44 wherein a region 110 of thelateral portion of soft tissue 100 adjacent to the previously formedconstruct is not pressed against underlying boney surface 200. If thesoft tissue within the region is not pressed to the boney surface, therepair may not result in complete reattachment of soft tissue 100 toboney surface 200. FIGS. 51 and 52 depict the distal portion of animplant placement system 4000 of the present invention configured forthe placement of a small diameter implant 4600. Implant placement system4000 is alike in all aspects of form and function to placement system3000 except as specifically hereafter described. Implant 4600 is formedpreferably of a high strength ceramic material. Ceramic implantssuitable for use in the context of the present invention are describedin detail in a related co-pending applications entitled “Ceramic ImplantPlacement Systems And Superelastic Suture Retention Loops For UseTherewith” Ser. No. 15/256,815 that was contemporaneously filed with theinstant application, the entire contents of which are herebyincorporated in their entirety.

Unlike implant 3600 wherein the torque-transmitting features are locatedin the lumen of implant 3600, the torque-transmitting features ofimplant 4600 are formed in the proximal end of implant 4600. Distalportion 4514 of distal torque-transmitting element 4512 has formed onits distal end, torque-transmitting features complementary to those ofimplant 4600. The torque-transmitting features of implant 4600 are alaterally extending channel, with a complementary rib formed on distalportion 4514 of distal torque-transmitting element 4512. In otherembodiments other complementary features are configured for torquetransmission. These features are configured so that torque iseffectively transmitted to implant 4600 for both insertion and removalfrom a socket. Due to the high strength ceramic material from whichimplant 4600 is formed and the unique proximal torque-transmittingfeatures of implant 4600 which this enables, implant 4600 may have aminiaturized small-diameter construction capable of knotlessly affixingsutures in locations in which such fixation would be precluded by thelarger footprint size of other knotless implants.

FIG. 50 depicts a double row construct of the present invention. Region110 wherein soft tissue 100 is not pressed against underlying boneysurface 200 is positioned adjacent to the construct. Tissue 100 withinregion 110 may be pressed to underlying boney surface 200 bysupplementing the construct of FIG. 50 with implant 4630. As depicted inFIG. 53, implant 1632 is removed from socket 204 and socket 206,configured to receive implant 4630, is formed a short distance fromsocket 204 and laterally aligned such that suture between implant 3630and anchor 4630 to be placed in socket 204 spans region 110 of softtissue 100. Thereafter, as depicted in FIG. 54, suture 340 is tensionedand affixed by implant 1632 as previously described. Suture 338 istensioned and affixed by implant 4630 in the manner previously hereindescribed, suture 338 spanning region 110 so as to press tissue 100therein against underlying boney surface 200. FIG. 55 depicts thecompleted augmented construct with the sutures trimmed.

FIG. 56 depicts an alternate construct wherein the region 110 is pressedagainst underlying boney surface 200 through supplementing of theoriginal construct depicted in FIG. 50. In this construct lateralimplant 4630 and a medial implant 4632 are added to the construct suchthat sutures 342 and 344 span region 110 so as to compress tissue 100therein against underlying boney surface 200.

Supplementing of a completed double row construct with one or moreadditional implants and one or more sutures coupled to the originalconstruct as previously described according to methods of the presentinvention, is enabled by the ability to remove implants of the originalconstruct so as to allow reconfiguration of the sutures of theconstruct. This reconfiguration allows sutures to span tissue in theregion between the original construct and the supplemental one or moreimplants. The ability to modify the construct is enabled by theremovability of the implants. This, in turn, is enabled by theconfiguration of implant systems of the present invention and thethreaded implants which secure suture in a socket by trapping the suturebetween the implant and at least a first portion of the socket wall.This is in contrast to the system of Green et al. wherein a two-pieceimplant system is used, sutures being fixedly secured by a separatefixation element to an anchor that is placed prior to suture tensioning.The implants of Green et al. cannot be readily removed after placementnor suture reconnected to an anchor. Similarly, the Burkhart implantsystem uses a first eyelet implant which is removably affixed to the endof the driver, and a second threaded implant which secures the eyelet inthe socket and accomplishes suture fixation by trapping the suturebetween this second securing implant and portions of the socket wall.Backing out the Burkhart implants after placement and removal of thedriver from the site so as to allow adjustment of the suture tension orrepositioning of the implant would require that the first eyelet implantbe reattached to the driver, a task which is impossible after the eyeletis removed from the driver. The adjustment of the tension in sutures ofa multi-implant construct or the backing out and re-seating of implantsof the construct are impossible with the Burkhart system.

Implant systems of the present invention enable the surgeon to establishsuitable tension in a suture prior to implant placement, and to maintainthat tension unchanged during implant placement. Accordingly, the needto adjust suture tension after implant placement is minimized. Incertain instances, this removability of an implant for adjustment of theassociated suture tension or repositioning of an anchor, whiledesirable, may not be necessary, or may be precluded by the requirementto place an irremovable push-in implant. Push-in implants of the presentinvention may be produced in very small sizes for applications in whicha very small footprint is required. Miniature push-in implants of thepresent invention may be formed of a high-strength ceramic material.

Implant placement system 5000, the distal portion of which is shown inFIGS. 57 and 58, is like implant system 4000 in all aspects of form andfunction except as specifically subsequently described. Implant 5600 hasformed on its outer surface a plurality of tapered portions that allowaxial insertion into a prepared socket and that resist proximal motionof the implant after placement. Because implant 5600 is pushed axiallyinto a socket, the torque-transmitting features of implant 4600 areeliminated and the proximal end surface of implant 5600 has a planarsurface, as does the distal surface of distal element 5512 of thedriver. Implant 5600 is placed in the same manner as other implants ofthe present invention except that, after tensioning of sutures to besecured thereby, implant 5600 is advanced to the socket and then placedtherein by the surgeon striking the proximal end of the driver with amallet so as to advance implant 5600 axially until implant 5600 is fullyseated. The tension in the suture secured by implant 5600 is not changedduring placement of implant 5600.

FIG. 59 depicts a two-anchor construct identical to the construct ofFIG. 38 in all aspects except as specifically hereafter described. Forexample, threaded anchor 1600 of the construct of FIG. 38 may bereplaced by push-in implant 5600 (FIGS. 57 and 58). The construct ofFIG. 59 is formed by the same method as the construct of FIG. 38 in allaspects except as specifically described hereafter. Following placementof medial implant 3600, suture 300 is tensioned as previously hereindescribed and secured by implant 5600 which is pushed in rather thanthreaded in like lateral implant 1600 of the construct of FIG. 38.Because lateral implant 5600 is not removable after placement,adjustment of the tension in suture 300 is not possible. Because thetension is established prior to the placement of implant 5600 and is notchanged during the placement of implant 5600, the tension in suture 300in the completed construct is as intended by the surgeon.

FIG. 60 depicts a multi-anchor repair construct formed using methods ofthe present invention wherein lateral anchors 5600 are push-in implantsplaced using system 5000 depicted in FIGS. 57 and 58. As in theconstruct depicted in FIG. 59, sutures 300 are tensioned prior toplacement of implants 5600. Implants 5600 are irremovable afterplacement using the elements of implant system 5000. The use of smalldiameter push-in implants 5600 may be necessitated by anatomies in whichan effective multi-anchor construct requires the use of implants whichhave a minimal footprint.

FIG. 61 depicts a multi-anchor construct in which the two medial andsingle lateral anchors are all small-diameter push-in implants 5600,sutures 300 being tensioned according to the principles of the presentinvention as previously described herein.

INDUSTRIAL APPLICABILITY

As noted previously, there is a need in the art for simplified placementsystems and fixation methods for tissue graft anchors by which thesurgeon may introduce one or more sutures into one or more socketsprepared in the boney tissue, apply tension to the sutures to advance asoft tissue graft to a desired location, and then advance the one ormore anchors into the bone while maintaining suture tension. The presentinvention addresses this need by providing systems and tissue fixationmethods that allows the surgeon to establish the graft position and,while maintaining that position, secure the anchor without changing thesuture tension or causing a shift in the graft position and furthermore,when the anchor is threaded, without spinning of the suture. The presentinvention further addresses the need for double row fixation methodsthat allow for each tissue-spanning suture to be individually tensionedprior to, and optionally after, if the original tension is deemedunsuitable, being removably affixed to the bone by an implant. Likewise,the present invention provides for the ready relocation of any anchorfound to be unsuitable as well as the placement one or more additionalimplants as needed to span the region with tensioned sutures. Althoughdescribed in detail with respect to ligament repairs, such as repair ofa torn rotator cuff, it will be readily apparent to the skilled artisanthat the utility of the present invention extends to other tissues andinjuries.

The disclosure of each publication, patent or patent applicationmentioned in this specification is specifically incorporated byreference herein in its entirety. However, nothing herein is to beconstrued as an admission that the invention is not entitled to antedatesuch disclosure by virtue of prior invention.

The invention has been illustrated by reference to specific examples andpreferred embodiments. However, it should be understood that theinvention is intended not to be limited by the foregoing description,but to be defined by the appended claims and their equivalents.

What is claimed:
 1. A method for affixing a soft tissue graft to atarget location on a boney surface, said method comprising the steps of:a. positioning said soft tissue graft on said boney surface at saidtarget location, wherein said soft tissue graft is characterized by alateral edge and top and bottom surfaces; b. providing at least oneelongate suture characterized by first and second free ends; c. securingsaid first free end of said suture to said boney surface by means of afirst implant inserted into said boney surface underneath said softtissue graft, at location that is medial to the lateral edge of saidsoft tissue graft; d. passing a first length of said suture thatincludes said second free end from said first implant over the topsurface of said soft tissue graft, such that said second free endextends away from said first implant; e. preparing a socket in saidboney surface at a predetermined location; f. establishing a desiredtension in said first length of said suture that is sufficient tocompress an area of the soft tissue graft to the boney surface that isdisposed between said first implant and said predetermined location; andg. after said desired tension is established in accordance with step (f)and using only a second implant of one-piece construction, placing saidsecond implant into said prepared socket so as to simultaneously fix theplacement of said second free end of said suture and compress at least aportion of said first length of said suture between an outer surface ofsaid second implant and a wall of said socket, whereby said desiredtension in said first length of suture is maintained throughout step(g).
 2. The method of claim 1, wherein the predetermined location ofsaid socket is medial to the lateral edge of said soft tissue graft. 3.The method of claim 1, wherein the predetermined location of said socketis lateral to the lateral edge of said soft tissue graft.
 4. The methodof claim 1, wherein said soft tissue graft is further secured to saidtarget boney surface by repeating steps b-h using third and optionallyfourth implants.
 5. The method of claim 4, wherein one of said secondand third implants is positioned medial to the lateral edge of said softtissue graft while the other is positioned lateral to the lateral edgeof said soft tissue graft.
 6. The method of claim 1, wherein said methodfurther comprises the step of adjusting the tension in said first lengthof suture after placement of said second implant.
 7. The method of claim6, wherein said tension adjustment is achieved by: a. proximallyretracting said second implant; b. adjusting the tension in said firstlength of suture; and c. distally advancing said second implant backinto said socket until said second free end of said suture is adequatelysecured between the outer surface of said second implant and the wall ofsaid socket and thus said first length of said suture is adequatelytensioned so as to provide fixation to said soft tissue graft.
 8. Themethod of claim 1, wherein said method further comprises the step ofrepositioning said second implant in said prepared socket.
 9. The methodof claim 8, wherein said repositioning step is achieved by: a. removingsaid second implant; b. forming a second socket in a secondpredetermined location; c. adjusting the tension in said first length ofsaid suture; and d. distally advancing said second implant into saidsecond socket until said second free end of said suture is adequatelysecured between the outer surface of said second implant and the wall ofsaid second socket and thus said first length of said suture isadequately tensioned so as to provide fixation to said soft tissuegraft.
 10. The method of claim 1, wherein said second implant iscannulated.
 11. The method of claim 10, wherein said second implantcomprises an interference plug-type anchor.
 12. The method of claim 10,wherein said second implant comprises a threaded anchor.
 13. The methodof claim 1, wherein said first implant is cannulated.
 14. The method ofclaim 13, wherein said first implant comprises an interference plug-typeanchor.
 15. The method of claim 13, wherein said first implant comprisesa threaded anchor.